package com.baichuan.example.unit_test

object ObjectMethod {

    fun doSomething() {
        println("this is ObjectMethod#doSomething")
    }

    @JvmStatic
    fun doSomethingWithJvmStatic() {
        println("this is ObjectMethod#doSomethingWithJvmStatic")
    }
}

  @Test
  @DisplayName("mock普通的kotlin靜態(tài)方法")
  fun testMockKotlinObject() {
      Assertions.assertThrows(MissingMethodInvocationException::class.java) {
          Mockito.mockStatic(ObjectMethod::class.java).`when`<Unit>(
              ObjectMethod::doSomething
          ).thenAnswer { println("this is mocked Object#doSomething") }
      }

      ObjectMethod.doSomething()
  }

public final class ObjectMethod {
   @NotNull
   public static final ObjectMethod INSTANCE = new ObjectMethod();

   private ObjectMethod() {
   }

   public final void doSomething() {
      String var1 = "this is ObjectMethod#doSomething";
      boolean var2 = false;
      System.out.println(var1);
   }

   @JvmStatic
   public static final void doSomethingWithJvmStatic() {
      String var0 = "this is ObjectMethod#doSomethingWithJvmStatic";
      boolean var1 = false;
      System.out.println(var0);
   }
}

	@Test
	@DisplayName("通過反射修改靜態(tài)常量來mock普通的kotlin靜態(tài)方法")
	fun testMockKotlinObjectMethodByReflection() {
	    val mock = Mockito.mock(ObjectMethod::class.java)
	    Mockito.`when`(mock.doSomething()).then {
	        print("this is mocked ObjectMethod by reflection")
	    }
	    val declaredMethod = ObjectMethod::class.java.getDeclaredField("INSTANCE")
	    ReflectionUtils.setFinalStatic(declaredMethod, mock)
	
	    ObjectMethod.doSomething()
	}

package com.baichuan.example.unit_test

import java.lang.reflect.Field
import java.lang.reflect.Modifier

object ReflectionUtils {
    @Throws(Exception::class)
    fun setFinalStatic(field: Field, newValue: Any) {
        field.isAccessible = true
        val modifiersField: Field = Field::class.java.getDeclaredField("modifiers")
        modifiersField.isAccessible = true
        modifiersField.setInt(field, field.modifiers and Modifier.FINAL.inv())
        field.set(null, newValue)
    }
}